This invention relates to the preparation of pre-coated, high-strength stainless steel and superalloy metallic components. More particularly, the present invention relates to the use of organic, corrosion-inhibiting coatings containing aluminum pigment to coal high-strength metallic corrosion-resistant stainless steel and heat-resistant superalloy materials used as aircraft structural components.
Aircraft manufacturers use a variety of different ferrous and non-ferrous metals in the fabrication of aircraft components. Commonly assigned U.S. Pat. Nos. 5,614,037; 5,858,133; 5,922,472; 5,944,918; 6,221,177, and 6,403,230 disclose methods for pre-treating aluminum-alloy articles to obviate the use of wet-sealants and other coatings for protection against corrosion damage. Pre-coated ferrous-alloy articles such as carbon steels and aircraft-quality low-alloy steels, for example; Aermet 100, Hy-Tuf™, 300M, H-11, HP9-4-30, 52100, 1095, 4130, 4135, 4140, 4330V, 4340, 6150, 8740, etc. are often used as structural aircraft components and are disclosed in U.S. Pat. Nos. 6,274,200 and 6,475,610. It had been known to protect ferrous-alloy components, which include fasteners, bearings, struts, etc. from wear and corrosion by applying an overplate of cadmium alone or in combination with a chrome plate. Previously, these fasteners were often installed using wet-sealant. While this use of wet-sealant and/or plated overcoat protected the various material substrates from corrosion, such wet-sealant installation and cadmium and chrome-plating processes are time consuming, cumbersome, expensive, and environmentally undesirable.
It would be extremely desirable to impart corrosion resistance to the high-strength stainless steel and superalloy metallic substrates obviating the need for the chrome and cadmium-plating and/or wet-sealant installation processes. It would be further highly desirable to incorporate the coating cure step into an existing alloy fabricating process.